Planetary milling machine



May 22, 1951 H. NORBERG ETAL 2,553,669

PLANETARY MILLING MACHINE Filed Nov. 13, 1947 7 Sheets-Sheet 1 1 I Er.3.1

I1-l INVENTOR. F 4 Ham/aA/orberg y L/oya L. Lee

A T TORNE Y5 May 22, 1951 H. NORBERG ETAL 2,553,669

PLANETARY MILLING MACHINE I Filed Nbv. 13, 1947 I 7 Sheets-Sheet 2 L. H.ln ferna/ L .H. -/nferna/ JNVENTOR. Harv/a Norberg BY Ha /d1. lee

y 22,1951 H. NORBERG ETAL 2,553,669

PLANETARY MILLING MACHINE Filed Nov. B 1947 '7 Sheets-Sheet 5 INVENTOR.Hare/a Norbe/y BY A/aydl. Lee

ATIGRNEYS M y 22, 1951 H. NORBERG ETAL 2,553,669

PLANETARY MILLING MACHINE Filed Nov. 13, 1947 7 Sheets-Sheet 4 80INVENTOR. Harald Norber r 5 BY M yo L. lee

HTTORNEV-f ai 1951 H. NORBERG ETAL 2,553,669

PLANETARY MILLING MACHINE Filed Nov. 13,1194? 7 Sheets-Sheet 5 w M R m 1A llvvizlvroa.

y 1951 H. NORBERG ETAL 2,553,669

PLANETARY MILLING MACHINE Filed Nov. 13, 1947 7 Sheets-Sheet 6 INVENTOR.Ham/a A/arbery BY L layd L. .4 es

4 TTORNEYS y ,1951 H. NORBERG E'l AL 2,553,669 PLANETARY MILLING MACHINEFiled Nov. 15, 1947 '7 Sheets-Sheet 7 I65 INVENTOR.

Ham/a /Vo/-ber A laya L. Lee

Patented May 22, 1 951 UNITED STATES PATENT OFFICE PLANETARY MILLINGMACHINE Harold Norberg and Lloyd L. Lee, Hazel Park, Mich., assignors toPlan-O-Mill Corporation, Hazel Park, Mich., a corporation of MichiganApplication November is, 1947, Serial No. 785,762

radially into the workthe depth of thethread...

after which a lead screw feeds the cutter through a distance of onethread as it moves in cutting relation around the surface to bethreaded. For a straight thread this lead or forward movement results inan accurate reproduction of the lead screw pitch. For a tapered thread,the lead or feed movement will result in an inaccurate thread unless thecutter is given an additional move-v ment in the direction of the taper.

It is an object of the present invention to disclose a machine forgiving this additional compensating movement in an accurate manner andin a manner which can be carefully controlled.

Brief description of the several views .of the drawings:

Figure 1 is an outline view of a planetary milling machine with a taperattachment thereon.

Figure 2 is an outline view of the milling head of the machine.

Figures Sand 4 illustrate the manner in which a cutter contacts the workfor tapered threading.

Figures 5, 6,7 and 8 are diagrammatic views showing a cam compensator invarious positions as used in the taper attachment.

Figure 9 is an elevation of the planetary milling head showing the partsin greater detail.

Figure 10 is a sectional view on line Ill-Ill of Figure 9.

Figure 11 is an expanded view of a gear chain,

8 Claims. (Cl. 9l)11.58)

In a planetary milling machine, a tool spindle S is mounted on suitablebearings for cutting.

rotation in an inner drive cylinder 30 (Figure 10) This spindle iseccentrically mounted in the inner drive cylinder. The inner drivecylinder is mounted eccentrically in suitable bushings in any outerdrive cylinder 40. The outer drive cylinder.

is mounted for rotation in sleeve bushings in a frame structure 50.

For the purposes of clarity, the parts in sectional figures, such asFigure 10, which due to their circular cross section appear at the topand bottom of the drawings wil be marked with reference characters atthe 130p and bottom.

On the face end of the inner drive cylinder 30,

secured by screws 3| is an adjustable do plate 32 which rotates with theinner drive cylinder.

Adjustable dogs 34, and 36, shown best in Figure; 9, are fixed by screws3! on the adjustable dog plate at predetermined locations as will belater; explained. The dog plate has holes tapped at a plurality ofpoints around its periphery to receive screws 31. On the face end of theouter drive cylinder 40 held on by a plurality of screws 4| is an outerdrive plate 42 which rotates with the When one of the dogs 34' tatingand due to the eccentric mounting of the" spindle S, the tool travels ina helical path.

This continues up to the time that one of the dogs of the inner drivecylinder contacts the outer drive cylinder and'the entire assembly re--Volve together. The tool then starts moving in a circular path whilestill rotating at a predetermined distance from the center of theassembly, and by this time it has reached its cutting position and istraveling around the work.

As the assembly rotates in the'frame 50, a lead screw comes into actionto feed the tool T in the proper forward movement for the thread beingcut. The lead screw is rotatably positioned around the outer drivecylinder 40. and bears on a ring 6| threaded on the end of member 40 andlocked by a clip MA. A lead screw nut 62 is fastened to the frame 50 bybolts 63. An adjusting nut 64 is interposed between the parts to take upplay resulting from wear and an adjusting nut lockplate 65 establishesthe relation between the parts. The fixed dog 44 has a rearwardextension 10 which passes through a slot In the present disclosure itwill be noted that I the plate 42 is slotted at II so that the rearwardextension 79 of dog 44 passes through the plate 42 to the lead screw.

Revolving force is transmitted iron; member .3!) to member 49 through amechanism which pornpensates for the taper of the thread being cut. Theso-called fixed dog 44, which is moved by dogs 34 or 36 on member 32, ismounted on a a rier plate 55 Whiehin turn is .rotatably mounted aroundthe adjustable dog plate 32, .Gibs .8I hold carrier plate 89 a ainst theouter drive plate 42. Qn the carrier plate are cam rollers 85 and 88(Fig. 11,) .On the .outer drive or quill plate 42 is mounted .a cam 9-9.ona cam shaft 92 in a bearns holder 9.3. Thus force by dog 35 on fixedcam 44 is exerted by roller 88 on cam Hi3 and thence to the outer quillplate 42 and to 40. Once h do 4.4 is p ked up by inner .quill 3n theleadscrew will rotate with the .do to give a straight dvance t the outerQuill.

But he relationship between the lead screw m vin with the drive member30 with respect o he dr ve or quill 49 maybe altered by changm he n tionof cam so. .A r ng sear I no is key d to the outside of lead screw not5.2 and sur ounde by a gear housing I115 secur d by quill plate 42. Achain f gea s is mounted in the ousi g. thcfirst of the chain I IIIcontacting the ring ear and the las of the chain us bein mounted on camshaft 92. All of the gears H0, III, 2, .I I. 3, HA, I I5, and EH aremounted beween the walls of ear housing IE5 and ge r housing cover plateI28 (Fig. ll) The gearihomr s rota s about th ring g ar and in so doinau s rotati n of th sear chain and a rotation Ojf cam 9.0.

Th cam 30 is .forme to shift the cutte i t direction of the taper.Whether the cutter is shifted toward or away from the work depends onwhether the cutter is making a conventional ut or a climb out. For eachb ch width the aperogress s a specified distanc radially. The cutteractually travels .a true spiral into a pitch c ne. h com s shaped tochange the relationship between the drive member 33 and the outer drivemember 48 a specified distance such that as the cutter moves axially thedistance of one pitch, it has actually shifted radially also. For eachthread pitch and each taper the rela tionship will be difierent and thecam will necessarily be different. In Figs. 3 and 4. the small arrowsindicate the direction of movement for conventional cutting. In Fig. 4,the small triangle is illustrative of the movement. If the side marked Prepresents pitch and the angle A is the taper, the tangent of the anglerepresents he proper radial mo men for each pitch.

In the operation when the inner drive quill I 30 starts to move carryingthe rotating cutter to its work position, the cam v34 or the cam 36depending on the direction of rotation will contact fixed dog .44. Theouter drive quill .40 then starts o move. At this time the cutter has.reached its 4. cutting position as shown, for example, in Fig. 3. Asquill 4i! rotates, the lead screw acts to shift the combined quills inpitch relation to the work. But as soon as quill 40 starts to rotate thegear train IIIlII6 starts to rotate cam 9!] moving with quill 46, whichcam bears against roller 85 or 88, depending on the direction ofrotation, the rollers bein mounted on Ithe inner quill 38. And the cam90 shifts the quill plate 32 to the extent that the cutter moves theradial amount of the taper in one pitch distance. This movement, in

effect, prevents the cutter from overcutting the threads as itprogresses on the taper cut. Figs. 3 and .4 illustrate by the arrows thecompound movement that must take place.

For reversal movement a reverse key IE2 is provided to start reversal ofall parts when dog 34 or 35 come into action. This reverse key may bemoved to one side or the other depending on the direction of the threadbeing cut and is provided to prevent roller cam contact in the reversemovement. In Figs. 5 to 3, various combinations are shown for internaland external cylinder I48. Frame structure I59 supports the parts forrotation.

On the face end of the inner drive cylinder I secured by screws I3] isan adjustable dog plate I32 which rotates with the inner drive cylinder.Adjustable dogs I34 .and I36, shown best in Fi 12., are fixed b screws I3! on the adjustable dog plate at predetermined locations. On the faceend of the outer drive cylinder I49, held in place by a plurality ofscrews MI is an outer drive plate I42 which rotates with the outer drivecylinder. Dog I44 is mounted on a carrier plate I89 in the path of dogsI34 and I36. A bolt I48 supported in dog I44 passes through the dog toengage a notch in the extending flange I 59 of a lead screw,

I60. A rearward extension I10 of dog I44 moves in an arcuate slot III inplate I 42 (Figs. 12, .13).

The lead screw I60 is positioned around the outer drive cylinder I48 andbears on a ring .IBI

threaded on the. end of member I40 and locked.

by clip I5IA. A lead screw nut I62 is fastened to the frame I50 by boltsI63. An adjusting nut I54 is interposed between the parts and anadlusting nut lockplate I65 establishes the relation between the parts.

The relationship between drive member I32 and the outer drive or quillI40 is governed by a crank arrangement in the embodiment of Fig. 12.

A ring gear 290is keyed to the outside of lead screw nut I62 and theouter quill plate I42 cooperates with a cover plate I43 to form a gear.

housing around the ring gear in which are mounted a chain of gears 2H],2H, 2I2, 2I3, 2I4, 2I5, 2IIi, 2II, 2I8, 2I9, and 229. Gear 2IIl engagesand is turned by ring gear 208. The last gear 220 of the chain ismounted on shaft I92 on which is mounted a crank wheel 250 (Fig. 14).Crank wheel 25!] is slotted at 25I to receive a slide 252 locked inposition by a headed pin 253 within shaft I92. cooperate with anadjusting screw 254 mounted along the slide in wheel 250.

A crank bar 260 is pinned to the slide 252 at one end and at the otherendto a radial exten f One side of slide 252 is racked to sion 262 ofthe'carrier plate I80 on which dog I is'mounted. Plate 263 serves as abearing fo'r'across pin 264 together with the extension 262.

Operation of this construction is much the same as the previousconstruction of Fig. 9. When inner quill I30 moves dog I36 on plate I32to contact dog I M, the motion of dog I 44 is transmitted to crank bar260 which will drag the outer quill plate I42 and gear hOllSll'lg formedtherewith.

. Movement of the gear housing will start'the gear chain in revolutionsince the lead screw I60;

and the ring gear fastened thereto are stationary with the frame I50.The gear chain will rotate crank wheel 250. If the point P representsthe center of the pin connecting crank bar 260 to slide 252, when P isat the center of wheel 250 there would be not change in the relationbetween the inner quill I30 and the outer quill I40. But when the slideis moved so that the point P is off center, then crank 260 will changethe relation of the outer quill radially with respect to the work.

The embodiment of Figs. 12, 13 has an advantage over the device shown inFigs. 9, 10, in that it may be adjusted over a wide range of pitches anddiameters. With the cam arrangement of Fig. 9, a different cam must beused for each thread cut.

What we claim is:

1. In a planetary milling machine of the type having an inner quill, anouter quill and a cutter spindle, a frame supporting the quills, a meansfor providing compensating movement in a taper thread out whichcomprises plates on the forward ends of each quill, a cam on the outerquill plate, a ring gear fastened to said frame, a gear chain connectingsaid cam and ring gear whereby said cam rotates upon movement of saidouter quill, an intermediate member between said plates and mounted onsaid outer quill plate adapted to be contacted by the inner quill plateand means on said intermediate member to be actuated by said cam tocause motion of said inner quill relative to said outer quill durin therotation of the parts to effect a spiral movement of the cutter spindlein a taper thread cut.

2. In a planetary milling machine of the type having an inner quill, anouter quill and a tool spindle within the inner quill, and a framesupporting said quills such that the tool spindle approaches a cuttingorbit upon movement of the inner quill and rotates in said orbit whenthe inner quill picks up the outer quill, means for compensating fortaper thread cuts which comprises a plate on the face end of each quill,a ring gear mounted on the frame, a crank wheel mounted on the outerquill plate, a gear chain mounted on said plate arranged in operativerelation between the crank wheel and the ring gear to be actuated byrelative movement between the outer quill plate and the frame, anintermediate member mounted between the inner quill plate and the outerquill plate adapted to be contacted by the inner quill plate as the toolspindle reaches its cutting orbit, and a crank bar connecting the crankwheel on the outer quill plate and the intermediate member wherebyrotation of said outer quill plate will effect relative movement of saidinner quill plate with respect to said outer quill plate to move thecutting spindle from the cutting orbit in a radial direction equal tothe taper cut.

3. A device as described in claim 2 in which the crank bar is connectedto the crank wheel by a member adjustably slidable in the crank wheeldiametrically thereof and means for controlling the position of saidsliding member relative to the center of the crank wheel.

4. In a planetary milling machine of the type having an inner quill, anouter quill, a tool spindle within the inner quill, a frame supportingsaid quills and a lead nut on said frame, a lead screw around said outerquill rotatably associated therewith and means for eifecting movement ofsaid tool spindle in a conical spiral cutting movement comprising anintermediate member positioned to be contacted by said inner spindle ata point in rotation, a member connectin said intermediate member" andsaid lead screw for simultaneous rotation with said inner spindle, andmeans connectin said intermediate member and said outer quill responsiveto movement of said outer quill to change the angular relation betweensaid intermediate member and said outer quill and thus between saidouter and inner quills, said change thereby shifting said tool spindleradially while moving with the lead screw, said connecting meanscomprising a cam on said outer quill, a ring gear on said frame, a gearchain connectin said rin gear and quill, and a cam roller on saidintermediate member transferring rotative force from said irmer quill tosaid outer quill through said cam.

5. In a planetary milling machine of the type having an inner quill, anouter quill, a tool spindle within the inner quill, a frame supportingsaid quills and a lead nut on said frame, a lead screw around said outerquill rotatably associated therewith and means for effecting movement ofsaid tool spindle in a conical spiral cutting movement comprising anintermediate member positioned to be contacted by said inner spindle ata point in rotation, a member connecting said intermediate member andsaid lead screw for simultaneous rotation with said inner spindle, andmeans connecting said intermediate member and said outer quillresponsive to movement of said outer quill to change the angularrelation between said intermediate member and said outer quill and thusbetween said outer and inner quills, said change thereby shifting saidtool spindle radially while moving with the lead screw, said connectingmeans comprising a crank wheel on said outer quill, a ring gear on saidframe, a gear chain connecting said ring gear and said wheel, and acrank bar connecting said wheel and said intermediate member to transferrotative force from said inner quill to said outer .quill.

6. A machine as described in claim 5 in which the crank bar is connectedto the crank wheel by a member adjustably slidable in the crank wheeldiametrically thereof, and means for controlling the position of saidsliding member relative to the center of the crank wheel.

7. In a planetary milling machine of the type having an inner quill, anouter quill, a cutter spindle, and a frame supporting the quills, ameans for providing compensating movement in a taper thread out whichcomprises mounting means on'the forward ends of each quill, a rotatingcam on the mounting means of the outer quill, a ring gear fastened tosaid frame, a gear chain connecting said cam and ring whereby said camrotates upon rotary movement of said outer quill, an intermediate membermounted on said outer quill and positioned to be shifted by said innerquill upon relative movement between the inner n out quills. and meanson said intermediate member to be actuated by said cam to cause motionof said inner quill relative to said outer quill during the rotation ofthe parts to efieet a spiral movement of the cutter spindle in a taperthread out.

'8. In a planetary milling machine of the type having an inner quill, anouter quill, a cutter spindle, and a frame supporting the quills, ameans for providing compensating movement in a taper thread out whichcomprises a mounting means on the forward end of said outer quill, arotatable member on the said mounting means positioned on an axisparallel to that of the quills, and means operably connecting saidmember and said frame whereby said member rotates upon movement of saidouter quill, an intermediate member mounted to shift with said innerquill,

and means connecting said rotatable member:-

and-said intermediate member to transmit rotary motion of said rotatablemember on the outer quill to relative rotary motion between said in-'REFERENCES CITED The following references are of record in th file ofthis patent: 2

UNITED STATES PATENTS Number Name Date 1,507,235 Hall Sept. 2, 192

2,266,338 Sheaffer Dec. 16, 1941;

